OAKLAND — Twenty-five people were arrested in Oakland on Tuesday after a day of protest against wealth inequality and for labor rights turned into a game of cat-and-mouse between police and demonstrators who clashed intermittently throughout the day.

Thousands of people flooded the streets of Oakland and San Francisco for what organizers billed as a May Day General Strike. The crowd — a mixed group of labor organizers and union members, supporters of the Occupy movement and others — ranged throughout the cities and staged rallies, many of them with a celebratory tone and feel.

But police moved in as night fell in Oakland and as many as 1,000 people remained on Frank H. Ogawa Plaza, the scene of earlier violent clashes with police and the Occupy movement. Police issued a dispersal order about 8 p.m., then said about 300 people surged forward and started throwing bottles and other objects at police. Someone set off a flash-bang grenade and police converged on the perimeter of the plaza and told protesters to leave. Protesters held their ground for a few minutes, and police spread out through the plaza and then protesters moved down toward Telegraph. Protesters lit an unmarked police car and some trash cans on fire as they went.

By about 10 p.m., some 50 to 100 protesters were back at 14th and Broadway and nearly as many police officers stood sentry on the other side of the street. As the crowd became rowdy, police used motorcycles and blared their sirens to move the protesters away from downtown. Police issued another dispersal order at 17th and Broadway, ordering people to leave the sidewalks and streets. Protesters seemed confused and many remained in the area while police retreated back to Ogawa Plaza — setting the stage for a night of show downs with demonstrators.

More than two dozen were arrested on charges of vandalism, resisting arrest, failure to disperse and violation of court orders to stay away from Ogawa Plaza, police Chief Howard Jordan said. At least three of those arrested were facing felony charges — one for assault and two for arson linked to a police car vandalism at 13th and Franklin streets and a car fire at 19th and Broadway.

Police weren’t reporting any major injuries to officers or protesters, but several people reported that at least one protester had been injured, with some saying a woman had been struck by something. Another demonstrator was injured when he fell during the march and struck his head on a metal grate in the roadway; he was taken to a hospital for treatment but was expected to be OK.

Early on, Jordan sent a clear message that police would not tolerate violence or vandalism.

“If people are intent on hurting other people or property we aren’t going to tolerate that,” Jordan said in an afternoon news conference.

Jordan characterized the protesters as “a lot more assertive, a lot more aggressive,” than those at Occupy Oakland protests over the last seven months.

In San Francisco, a large group of protesters took over the San Francisco Archdiocese at 888 Turk St., at Gough Street, vowing to turn it into a commune. Tuesday afternoon, one masked protester hurled and pipes bricks down from the rooftop onto the crowd below for several minutes, striking one man in the chest. That man received a bloody nose, but declined medical attention. Police surrounded the building and arrested the brick thrower when he came down, said San Francisco police Chief Greg Suhr. Protesters shouted that the masked brick thrower didn’t represent their movement. Police did not release the man’s name or age.

In Oakland earlier in the day, thousands walked miles from the Fruitvale district and other parts of the city for the culmination of an evening rally at Ogawa Plaza. As they made their way from the Fruitvale to San Antonio Park at 1700 Foothill Blvd. to downtown, at least five vans with police in riot gear were stationed along the route. When protesters arrived, they sang, danced, gave speeches and stood around.

Through out the day, protesters repeatedly scuffled with police in riot gear, who responded with tear-gas and orders to clear the streets. At least four people were arrested shortly after noon at 14th and Broadway when the crowd started throwing items at officers, who launched tear gas and used batons to subdue some demonstrators.

A Bank of America branch near the Kaiser Center and a Bank of the West at 2127 Broadway were spray painted with graffiti and there was other minor vandalism early in the day, police said. An OPD van had a windows broken and a news media vehicle had tires punctured, as well. Windows were also broken at a Wells Fargo branch on 20th and Franklin, and car was lit on fire near Ogawa Plaza.

Some protesters said the violence detracted from the message.

“As much as I support (the Occupy movement), there are a lot of legitimate reasons why it’s not being taken seriously,” said Sunny Hamilton, 25, of Castro Valley, “It’s not the message, it’s the method.

“Activism is a beautiful thing,” she said, “but roughing up a statue or hitting someone on the head with a bottle is not.”

Oakland police are receiving aid from the California Highway Police as well as the Hayward, Newark, Fremont and Union City police and the Alameda County Sheriff’s Office. Jordan said officers would not hesitate to use force if necessary.

In San Francisco, the take over of the archdiocese building was the culmination of a day of protests in the city. Occupiers had been evicted from the same building last month.

“We’re not the 1 percent,” said Archdiocese of San Francisco spokesman George Wesolek. “So why are they doing this to us?”

A spokesman says the protesters are not welcome and police will be asked to remove them as soon as possible. Still, Occupiers reiterated their plans to use the space as a community center and headquarters for their movement.

“It’s great,” said Ted Gullicksen, head of the San Francisco Tenants Union, who observed the take over. “I think public agencies and the church have a duty to make sure the people’s needs are being met.”

Earlier in the day, in San Francisco, suspended San Francisco Sheriff Ross Mirkarimi showed up to support the protesters, saying, “It’s an important message the country should hear. This frustration doesn’t just occur today, but all year round.”

In the North Bay, the Golden Gate Ferries were shut down for several hours Tuesday, but they reopened at 2:15 p.m. Ferry workers said they have been negotiating a new contract with Golden Gate Bridge management for a year, without success.

Katy Murphy is based in Sacramento and covers state government for The Mercury News and East Bay Times, a beat she took on in January 2017. Before that, she was the news organization's higher education reporter, writing about UC, CSU, community colleges and private colleges. Long ago, she covered Oakland schools and other K-12 education issues.

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